Extraction Unit and Method for Ventilating a Cooking Surface

ABSTRACT

An extraction unit for ventilating a cooking surface is provided that includes a retractable device permitting an extraction component of the extraction unit to be extended and retracted, a control unit comprising at least one actuating component, which is used to trigger the retractable device by a manual user entry, and a fan unit. The fan unit can also be controlled by the control unit, by means of the manual user entry for the actuating component. In addition, the actuating component can be configured as a rotary component, allowing at least one additional function of the extraction device to be controlled by the user by the rotation of the actuating component. The actuating component can also adopt a lowered position when the extraction unit is inactive and a position, in which it protrudes from the control unit, when the extraction unit is active.

The present invention relates to an extraction unit for ventilating a cooking surface, comprising a retraction device with which at least one extraction component of the extraction unit can be extended, a control unit comprising at least one actuating component which is used to trigger the retraction device by a manual user entry, and a fan unit. The present invention also relates to a corresponding method for ventilating a cooking surface.

The extraction component of a fume extraction hood can, for example, comprise an extraction screen which is extended or retracted in response to a user input. This is used to save space after switching off the fume extraction hood. This also helps to prevent accidents such as can occur as a result of a person bumping into the extended extraction screen. In addition, the risk of damage to the extraction screen during the inactive phase of the fume extraction device can thereby be reduced. However, it is important that the extraction screen is extended again before switching on the fume extraction hood 1 since the fume extraction hood can only function fully when the extraction screen is extended.

An actuating component is usually attached to the control device of the fume extraction device for a user to input an extension or retraction command relating to the retraction device. Furthermore, the fume extraction hood has further actuating components for control. Control of the fume extraction device by the plurality of actuating components can be very confusing for the user. This can in turn result in the necessary control command being forgotten or the control device being incorrectly operated.

Document DE 36 03 028 A1 proposes controlling the retraction device and the fan device simultaneously by means of a sensor arranged on the fume hood. However, this requires the attachment of a sensor device to the fume extraction hood which incurs additional costs for the device. In addition, the user cannot control the fume extraction hood himself in this case.

The object of the present invention is therefore to configure the control of the retraction device and the fan unit more simply for the user.

According to the invention, this object is achieved by an extraction unit for ventilating a cooking surface, comprising a retraction device with which at least one extraction component of the extraction unit can be extended and retracted, a control unit comprising at least one actuating component which is used to trigger the retraction device by a manual user input, and a fan unit wherein the fan unit can also be controlled by the control unit by means of the manual user input for the actuating component.

In addition, the invention also provides a method for ventilating a cooking surface by manual input of a command by a user and extension of at least one extraction component depending on the command, as well as triggering at least one fan unit depending on the same command.

The retraction device can thus advantageously be triggered by a manual input of a user without an additional actuating component needing to be attached to the control device. The retraction device and fan unit are activated or deactivated by means of the same actuating component. By eliminating an additional actuating component, the operating device of the fume extraction unit is easier for the user to view and easier to operate. In addition, the user does not need to actuate another actuating component. The solution proposed here also eliminates the costs for a sensor device.

The control unit advantageously comprises two microswitches which can be switched at the same time to reverse the polarisation of at least one lifting motor of the retraction device. As a result, the retraction device can be easily and reliably controlled.

In particular, the actuating component can be a pressure switch. In this way, the user can rapidly and simply actuate the manual input for activating the retraction device and for starting the fan unit.

According to the invention, the actuating component can be configured as a rotary component so that at least one additional function of the extraction unit can be controlled by means of a rotation of the actuating component by the user. This saves the application of at least one further actuating component to the control device of the fume extraction unit, thereby reduces the costs for the device and makes the operating device easier to view and easier to operate. In this case, the actuating component can comprise a rotary switch or a pressure rotary switch.

For example, the additional function is controlling the power stages of the fan unit. Such a control concept is easily understandable for a user and leads to the avoidance of errors during a manual input to the control device.

The pressure switch can advantageously occupy at least two positions with respect to the control device, the pressure switch being transferable by the pressure signal from one position to another position. Thus, the pressure switch can be in a lowered position when the extraction unit is inactive and in a position in which it protrudes from the control unit when the extraction unit is active. In this way, accidents caused by a person bumping into the input components protruding from the control panel can be avoided.

According to the function, the control units can comprise at least one rotary knob component which can be lowered. In this case, a depressible rotary knob can be combined with the conventional, electromechanical switching elements to form a control component which approximately provides the function of the more expensive electronic circuits. An inexpensive, electromechanical control concept which is easy to operate is thus achieved. The control concept can be used for extraction systems with vertical and horizontal retraction devices.

The present invention is now explained in detail with reference to the appended drawings in which:

FIG. 1 is a fume extraction device with retracted extraction screen before switching on;

FIG. 2 is a fume extraction device with extended extraction screen before switching off;

FIG. 3 is a fume extraction device with extended extraction screen during switching off;

FIG. 4 is a cross-section through a control device with a depressible rotary knob before switching on; and

FIG. 5 is a cross-section through a control device with a depressible rotary knob after switching off.

The exemplary embodiments from FIGS. 1 to 5 explained in detail hereinafter are preferred embodiments of the present invention.

FIG. 1 is a partial section of a fume extraction hood 1. In this case, the fume extraction hood 1 has an extraction screen 3 and a retraction unit. The retraction unit can extend the extraction screen 3 of the fume extraction hood 1 before it is activated so that the fume extraction hood 1 can function fully. When the fume extraction hood 1 is not required, the extraction screen 3 can be retracted again by means of the retraction unit so that more working space is provided close to the cooking surface for the person working there. In addition, accidents caused by a person bumping into the extraction screen 3 can also be prevented.

Since the fume extraction hood 1 is switched off in the example from FIG. 1, the extraction screen 3 is also retracted and therefore not shown in FIG. 1. Only the screen 2 behind which the extraction screen 3 lies hidden can be seen. In this case, the screen 2 serves as visual protection.

FIG. 1 also shows the actuating component 4 of the control device for triggering the retraction device of the extraction screen 3 and for controlling the fan unit 7. For the examples shown in FIGS. 1 to 5, a depressible rotary knob 4 was selected as the actuating component 4. The user can make a manual input by means of this actuating component 4 both by turning this depressible rotary knob 4 by a certain angle and also by exerting pressure by which means the position of the rotary knob 4 is shifted perpendicularly with respect to a control panel. Since several inputs to the appliance controller of a household appliance can be made by means of a depressible rotary knob 4, the number of input elements on the control panel of a household appliance can be minimised by using rotary knobs.

The depressible rotary knob 4 from FIG. 1 is a combination of a pressure and a rotary switch. The pressure switch can control the extension or retraction of the extraction screen 3 and the activation or deactivation of the fan unit 7 at the same time. The user can set the power stage for the fan unit 7 by turning the depressible rotary knob 4.

As shown in FIG. 1, the rotary knob 4 is depressed before a manual input for activating the fume extraction hood 1 in the screen 2. This prevents possible injury to a person by accidentally bumping against the rotary knob 4. It is also advantageous for the user that as a result of the depressed position of the rotary knob 4, said rotary knob 4 cannot be accidentally turned by a person bumping into it.

In addition, the control device of the fume extraction hood 1 can have other control elements which can be used to control further functions of the fume extraction hood 1. However, this is not essential. For better clarity, other control elements were not indicated in FIG. 1.

Also not shown in FIG. 1 is a symbol applied to the depressible rotary knob 4 which explains to the user the function of the rotary knob 4 with respect to the retraction device and the control device of the fume extraction hood 1. In addition, the depressible rotary knob 4 can be configured in such a manner that a user can clearly see that he has to press this for a manual input.

FIG. 2 shows what happens when the depressible rotary knob 4 is depressed by a user. In this case, the rotary knob is transferred by the pressing movement exerted on it from its first depressed position in the screen 2 into a second position. In this second position, the rotary knob 4 projects so far from the screen 2 that the fingers of a user can conveniently hold onto its lateral surfaces.

The electrical or mechanical retraction device is activated by the same pressing movement on the rotary knob 4 which shifts the position of the rotary knob 4. The extraction screen 3 extends. Various possibilities exist with regard to the direction of extension depending on the fume extraction hood 1. Thus, a fume extraction hood 1 can have a vertically movable extraction screen 3. A corresponding fume extraction hood 1 is then preferably arranged on the rear side of the cooking surface or on one of the two sides of the cooking surface. However, a fume extraction hood 1 can also have a horizontally movable extraction screen 3. This type of fume extraction hood 1 is then preferably arranged in the form of a flat screen hood above the cooking surface.

When the extension process is completed, the fan unit 7 switches on automatically. In this case, a control system of the fume extraction hood 1 from the example in FIGS. 1 to 3 for the fan unit 7 sets the power stage in which the fume extraction hood 1 was last operated before switching off. However, the power stage specified by the manufacturer can also be set automatically for the fan unit 7.

However, if the user is not satisfied with this power stage, he can correct this by turning the rotary knob 4. Depending on the type of appliance of the fume extraction hood 1, a plurality of power stages are available to the user. The lettering applied close to the depressible rotary knob 4 allows the user to set the power stage of the fan unit 7 by turning the rotary knob 4 in such a manner that it best meets his needs.

The extraction screen 3 has an extraction opening 5 for extracting the air. In order to avoid contamination of the fan unit 7, the extraction opening 5 is covered with at least one filter 6. In the fume extraction hood 1 in FIGS. 1 to 3, the extraction opening 5 is covered with two filters 6. Grease filters are particularly well suited for this purpose since greasy vapours frequently occur during cooking and roasting. The sucked-in air is then sucked in the sucking-in direction 9 shown in FIG. 2 from the extraction opening 5 to the fan unit 7. An extraction pipe fixing ring 8 is located close to the fan unit 7. An extraction pipe not shown in FIGS. 1 to 3 can be fixed to this extraction pipe fixing ring 8. The sucked-in air is then passed in the extraction direction 10 through the extraction pipe back into the external surroundings of the fume extraction hood 1.

The fume extraction hood 1 extracts air over a cooking surface until the user actuates a further input on the depressible rotary knob 4 for switching off the fume extraction hood 1. The rotary knob 4 protruding from the screen 2 is also pressed for this purpose. As shown in FIG. 3, the depressible rotary knob 4 is transferred from its protruding position back into its depressed position by means of the pressing movement. The fume extraction hood 1 is also switched off immediately when there is a pressure signal at the rotary knob 4. According to the invention, the retraction device is also activated in this case, thus starting the retraction of the extraction screen 3 back into its position from FIG. 1. As an additional function, the power stage in which the fan unit 7 was last operated can be retained. After the fan unit 7 is re-activated, this is switched precisely in the retained power stage.

The extraction screen 3 of the fume extraction hood 1 remains retracted until a user again requires the function of the fume extraction hood 1 and for this purpose again exerts a pressing movement on the depressible rotary knob 4. Once this has taken place, the retraction device and the fan unit 7 are started again and the process described in FIGS. 1 to 3 is repeated.

FIG. 4 shows an example of a control device with a depressible rotary knob 4 in cross-section. In FIG. 4, the depressible rotary knob 4 is shown in its rest position before a manual actuation to activate the fume extraction hood 1. The control device can be connected to a fume extraction hood 1 by means of a plug connection 12.

In this example also, the depressible pressure knob is a combination of a changeover switch and a rotary switch 11. In this case, the function of the changeover switch comprises retracting and extending the extraction screen 3, for which the polarity of the lifting motor must be reversed. This function can be implemented by the switch elements located close to the depressible rotary knob 4. In the example from FIG. 1, the control device has two microswitches 13 which can be switched at the same time, for this purpose but a two-pole changeover switch would also be possible.

In the depressed position of the rotary knob 4, a rotary knob rod 14 on the rotary knob 4 actuates switch elements arranged in parallel. The current profile is directed such that the lifting motor retracts the extraction screen 3. In the protruding position of the rotary knob 4 as shown in FIG. 5, the switch elements are unactuated, the current flow runs in the opposite direction and the extraction screen 3 extends.

A rotary switch 11 which is moved by means of a pressure switched coupled to a driving mechanism serves as a switch for the fan unit 7.

In this control device, all the switches are mounted on a board 15. A rectifier for a DC lifting motor is also placed on the board 15. This compact design can obviate the need for additional components. The compact pre-assembly of the individual components on the board 15 which is encapsulated in a plastic housing allows easy assembly. In addition, a board for a rectifier can be eliminated since the printed circuit board 15 is already used for this purpose. 

1-11. (canceled)
 12. An extraction unit for ventilating a cooking surface, comprising: a fan unit for providing a motive force for effecting the evacuation movement of a fluid away from a cooking surface; a retraction device having at least one extraction component of the extraction unit movable between an extended position in which the at least one extraction component of the extraction unit is positioned for receiving fluid being evacuated and a retracted position in which the at least one extraction component of the extraction unit is not positioned for receiving fluid being evacuated; and a control device having at least one actuating component manipulable by a manual user input, the control device controlling an operation of the retraction device in response to a manipulation of the at least one actuating component via a manual user input, the fan unit being operatively connected to the control device such that the control device both controls an operation of the retraction device in response to a a given manipulation of the at least one actuating component via a manual user input and controls as well an operation of the fan unit in response to the same given manipulation of the at least one actuating component via the manual user input.
 13. The extraction unit according to claim 12, wherein the control device includes two microswitches that can be switched at the same time to reverse the polarity of at least one lifting motor of the retraction device.
 14. The extraction unit according to claim 12, wherein the at least one actuating component of the control device is a pressure switch.
 15. The extraction unit according to claim 12, wherein the at least one actuating component of the control device is configured as a rotary component so that at least one additional function of the extraction unit can be controlled by means of a rotation of the at least one actuating component of the control device by a user.
 16. The extraction unit according to claim 15, wherein extraction unit includes means for controlling power stages of the fan unit and the additional function is controlling the power stages of the fan unit.
 17. The extraction unit according to claim 14, wherein the pressure switch can occupy at least two positions with respect to the control device and wherein the pressure switch can be transferred by a pressure signal from one position to another position.
 18. The extraction unit according to claim 17, wherein the pressure switch is in a lowered position when the extraction unit is inactive and in a position in which in protrudes from the control unit when the extraction unit is active.
 19. The extraction unit according to claim 12, wherein the control device includes at least one rotary knob component that can be lowered.
 20. A method for ventilating a cooking surface, the method comprising: providing a manual input by a user representative of a command; extending at least one extraction component in response to the given command represented by a respective manual input; and controlling an operation of at least one fan unit in response to the same given command represented by the respective manual input.
 21. The method according to claim 20 and further comprising applying a pressure signal to an actuating component to input the command by the user.
 22. The method according to claim 21 and further comprising controlling a further function relating to ventilation of a cooking surface in response to rotation of the actuating component by a user. 